Webster's Revised Unabridged Dictionary · 1913

Lethe

Lethe (lē"the o lēth) , noun

[See Lethal.]

Death. [Obsolete] — Shakespeare

Lethe (lē"the) , noun

[Latin, from Greek lh`qh, prop., forgetfulness; akin to lanqa`nesqai to forget, lanqa`nein to escape notice.]

1.
(Class. Mythology) A river of Hades whose waters when drunk caused forgetfulness of the past.
2.
Oblivion; a draught of oblivion; forgetfulness.